1. Field of the Invention
The present invention relates to a liquid crystal display element formed by bonding a planar micro-lens array onto a liquid crystal panel.
2. Description of Related Art
As shown in FIGS. 7 and 8, a liquid crystal display element is formed by bonding a planar microlen array 200 onto a liquid crystal panel 100. A gap is formed between the glass substrates 101 and 102 by a spacer 103. The liquid crystal 105 is poured into the gap. On a surface of the glass substrate 101, opposing a electrodes 101a are formed on the side of the liquid crystal 105. On a surface of the other glass substrate 102 transparent pixel electrodes 102a are formed on the side of the liquid crystal 105. Further, additional portions other than the transparent pixel electrodes 102a are formed which are not transparent, such as wiring, TFTS (thin film transistors), etc.
Recessed portions are formed on the glass substrate 201. A resin of high refractive index is filled into and cured in the recessed portions, thereby obtaining a large number (a plurality) of small convex lens 202 which are bonded onto the liquid crystal panel 100 by a bond comprising a resin of low refractive index. The low refractive index serves to focus irradiated light through each of the plural convex lens into pixel electrodes (i.e., openings for the pixels) 102a, so as to increase the brightness of an image projected upon the screen.
As another method of providing a large number of convex lens in the planar micro-lens array, the plural microlenses can also be directly formed a stamper by performing a stamping process on the surface of a glass substrate without forming recessed portions on the glass substrate.
In the case of bonding a planar micro-lens array 200 onto a liquid crystal panel 100, if the position is off or if the two are misaligned, it becomes impossible to obtain correct focusing of the light irradiated onto the pixel electrodes (i.e., the openings for the pixels) 102a. 
Therefore, in the conventional art, marks 203 are formed in four corners at the same time when a large number of convex lens 202 are formed i.e., sequentially. As shown in FIG. 8, a planar microlens array 200 and a liquid crystal panel 100 are made to fit together by aligning marks 104 with the marks 203, in which the marks 104 are formed on the bonding surface of the liquid crystal panel 100 in advance.
The marks 203, formed on the side of the planar microlens array 200, are formed with a resin of high refractive index. Therefore the marks 104 on the side of the liquid crystal panel 100 can be seen through the marks 203 which act as convex lens. As a result, it is difficult to fit the marks exactly.
To resolve the problem described above, the present invention includes a liquid crystal display element formed by bonding a planar microlens array onto a liquid crystal panel, comprising a plurality of convex lens and a first mark formed on the surface of said planar microlens array with a resin of high refractive index, and a second mark which corresponds to the first mark on the planar microlens array formed on the surface of the liquid crystal panel, wherein said first and second marks have corresponding forms so as to precisely fit and align the planar microlens array with the liquid crystal panel, by placing one of the first mark and the second mark into the space formed with the other of the first and the second mark.
The second mark on the side of the liquid crystal panel can be seen through the flat part which does not act as a lens of the planar microlens array, and therefore, easily aligning the planar array and panel.